VRC2000 Installation and Operations Manual Page 83
Technical or Setup Assistance
Telephone: 800.945.7730 (USA) or 801.975.7200 (worldwide) • Worldwide Web @ http://www.gentner.com
The VRC2000 is a highly specialized device. Repair and maintenance should
always be done by fully qualified service technicians.
CIRCUIT NOTE:
The VRC2000 contains CMOS integrated circuits. Any internal service should
only be attempted ine a static-free environment.
General Treatment
The VRC2000 is designed to operate in conditions typical of transmitter/
remote sites. The unit should be kept clean and dry to prevent damage. When
transporting the VRC2000, Gentner Communications recommends using a
static-free case or bag.
Troubleshooting
This section provides details in locating minor problems with a VRC2000.
The following measurements can help diagnose problems. Please read the
warranty in Section Two of this manual before attempting to field service a
VRC2000.
• Power Supply
Typical Readings
J7 Pin 1 = 10Vdc Digital Regulator Input
J7 Pin 3 = 20Vdc Positive Analog Regulator Input
J7 Pin 4 = -20Vdc Negative Analog Regulator Input
U23 Pin 40 = 4.8–5.2Vdc Digital Supply
U32 Pin 1 = 11.7–12.3Vdc Positive Analog Supply
U46 Pin 4 = -11.7–-12.3Vdc Negative Analog Supply
Battery OFF position = 3.6VdcRAM, Clock Backup
Repair Procedure (If Necessary)
Power-supply problems are typically incorrectly determined to be faulty
regulators. The actual cause of most power-supply problem is a bad
integrated circuit, which causes the regulator(s) to dissipate an abnormal
amount of power, or even shut down.
The digital supply-to-circuit ground continuity is from 200–300 Ohms.
A readings lower than 200 Ohms (with the power OFF), indicates an
integrated-circuit failure.
Metering-System Failure Alarms. Metering-system failure system
alarms can be generated by dirty AC power. Verify that the AC ripple on
the analog supplies is less than 30mV if the VRC2000 reports these
alarms.
• Processor Preset
Typical Readings
U23 Pin 1 = 5Vdc
Repair Procedure (If Necessary)
Check the reset circuitry. The VRC2000 automatically holds its
processor in reset if the AC line input drops below 72Vac RMS.
Maintenance and
Service
To Next Page
Loading...